Introduction: Objective assessments of peri-operative risk with spine surgery are necessary to improve surgical risk stratification. Morphometric analysis is an emerging tool with proven utility in predicting postoperative morbidity and mortality in other surgical disciplines. This study evaluates whether morphometrics can be used as a reliable predictor of peri-operative morbidity in male patients undergoing lumbar spine surgery.
Methods: The perioperative course of 192 male patients who underwent lumbar surgery at our institution from 2013-2014 was retrospectively reviewed. Pre-operative risk factors such as age, diabetes, smoking, CAD, and BMI were noted. Primary outcomes included 90 day post-op mortality and morbidity including: unplanned return to OR, 30 and 90 day hospital re-admission, surgical site infection, wound dehiscence, new neurological deficit, DVT, PE, MI, UTI, urinary retention, hospital acquired pneumonia, stroke, and prolonged ICU stay. Psoas muscle area at L4 was measured on preoperative MRI. Total psoas area was divided into tertiles to stratify psoas size as a predictor of complications.
Results: There was no difference in rate of complication comparing age, diabetes, smoking, CAD, or BMI. Psoas area was the only pre-operative marker that had any correlation with complications. Male patients with smaller total psoas area were more likely to have postoperative complications (27.43±7.45 versus 30.86±8.68, p=0.014). Male patients in the lowest tertile of psoas muscle size had a higher complication rate (39.3%) versus those in the middle (16.4%) and highest tertiles (21.9%) (p=0.008). Males in the lowest tertile had an odds ratio of 2.76 (p=0.002) of developing a complication as compared to the other two tertiles. The odds ratio using multivariate analysis to adjust for potential confounders was 2.42 (p=0.016).
Conclusions: The morphometric measurement of psoas muscle size can be a more sensitive predictive tool compared to other risk factors for perioperative morbidity in male patients undergoing lumbar surgery.
Patient Care: My research will improve patient care by helping to identify those patients who are most likely to have a postoperative complications after lumbar spine surgery.
Learning Objectives: By the conclusion of this session, participants should be able to: 1) Describe what is morphometrics; 2) Understand the utility of morphometrics in predicting patient outcomes after surgery; 3) Understand how morphometrics can be applied to spinal surgery